Piston for hydraulic cylinders.



' A. B. HASWELL. PISTON FOR HYDRAULIC CYLINDERS.

APPLICATION FILED APR. I8, 19!]- IfifiIfifiSh.

Patented Apr. 30, 1918.

2 SHEETS-SHEET I.

V I n Mk :5. 54 WEI/W A. B. HASWELL.

PISTON FO R HYDRAULEC CYLINDERS. APPUCATION FILED AP 18. 1912.

2 SHEETSSHEET 2- Cir mare an rr fii :WQ

ARTHUR B. 'HAswnLL, or ENSLEY,'ALABAMA.

PISTON roe HYDnA LIooYLINnnns;

memes.

To allwhom it may concern:

Be'it known that I, ARTHUR B. HAswELn, a citizen of the United States,residing at Ensley, in the county of Jefferson, State of Alabama, haveinvented certain new and useful Improvements in Pistons for HydraulicCylinders, of which the following is a specification.

My invention relates to an improved piston for hydraulic cylinders,comprising a series of brass or soft metal split piston rings which inturn are expanded by a series of wedges, spaced'at equal intervals aboutthe circumference of the piston thimble or center, and the objects of myimprovement are, first, to make the use of metallic packingpracticable-;second, to make it possible to adjust same without removingthe iston from the cylinder ;third, to reduce the cost of repacking, theloss of time on operation and loss of water on leaky cylinders.

The accompanying drawings illustratean embodiment of my invention.

Figure 1 is a longitudinal section on the assembled piston.

Fig. 2 is an elevation of the center of the piston.

Fig. ririgs.

Fig.

Fig.

Fig. key.

Fig. 8 is a longitudinal section of another construction of theassembled piston.

The piston in its preferred embodiment comprises the combined rod 1 andcenter 2. This center is provided with three or more slots (four in thecase illustrated) or keyways 3, spaced at equal intervals about itscircumference. On this center are placed the piston rings a which aresplit for the purpose of expansion, as shown at 5 (Figs. 3 and 4), andwhich are held in place by the followers 6 and 7. Follower 7 ispreferably screwed on the piston rod 1 and fastened in place. Follower 6is placed on theopposite end of the piston, after tapered keys 8 are 3is an elevation of one of the piston i is a section thereof.

5 is an elevation of one of the liners. 6 is an edge view of a group ofliners. 7 is a perspective View of a tapered Specification of LettersTatent, Application filed April 18, 1917. Seria1No.162,878; j- ,1

inserted in their respective slots 3, and held in place by nut 9.

In operation the piston is assembled as described above. ,"When new thesplit piston rings 4 are made a slip-fit in the cylinder; therefore, fora time the leakage is nominal. As soon as rings at wear an excessiveleakage takes place. The back cylinder head is removed and the follower6 is taken from they piston by first removing nut 9. Next in the annulargroove provided in follower 6 is placed one of the liners 1.0, itsthickness depending upon the amount that the rings 4: are worn. Follower 6 is now replaced on piston and forced to shoulder on center 2by screwing on nut 9. This causes tapered keys 8 to travel forward theexact thickness of the liner 10 and in turn forces piston rings at outto the cylinder wall. This operation is repeated until keys 8 havetraveled their maximum and rings 4 have worn to their minimum thickness.

Gare should be taken never to insert liners 10 unless it be possible toshoulder follower 6 against center If clearance is left between them thepiston rings l are free to separate the same amount and leakage occurs.

Although it is preferred to make the rod 1 and center 2 a unit. I findin practice that it is often impossible. In Fig. 8 there is shown apiston, the rod 11 of which is too large for the construction abovedescribed.

This difiieulty is overcome by making the rod 11 and the center 12 ofseparate pieces as shown.

With reference to the tapped holes 13 (Figs. 1. and 8) these are for eyebolts. To remove follower 6 from the cylinder, eye bolts are screwedinto these tapped holes. By this means follower 6 can be drawn from thecylinder without removing the entire piston.

Though I have described a certain specific embodiment of my inventionyet it-is not to be understood therefrom that it is restricted to thespecific embodiment disclosed. vanou's modifications in detail and inthe arrangement of the parts may be made by those'skilled in the artwithout departure from the invention as defined in the following claims.

What I claim is 1. In a piston, a series of split piston rings, a seriesof tapered keys, a liner and a back follower for forcing said taperedkeys forward to expand said series of rings.

2. In a piston, a series of split piston rings, a series bf taperedkeys, :1 back fol- 10 pered keys forivard to expand said series ofpiston rings.

In witness whereof, I have hereunto signed 15 my name.

ARTHUR B. HASWELL.

